Buggy code:
public class TagManager implements Listener { private static class TagContext { public final dPlayer player ; public final dNPC npc ; public final boolean instant ; public final ScriptEntry entry ; public final boolean debug ; public TagContext ( dPlayer player , dNPC npc , boolean instant , ScriptEntry entry , boolean debug ) { } } public Denizen denizen ; public TagManager ( Denizen denizen ) { } public void registerCoreTags ( ) { } public static String cleanOutput ( String input ) { } public static String cleanOutputFully ( String input ) { } public static String escapeOutput ( String input ) { } @ EventHandler public void fetchObject ( ReplaceableTagEvent event ) { } public static String tag ( dPlayer player , dNPC npc , String arg ) { } public static String tag ( dPlayer player , dNPC npc , String arg , boolean instant ) { } public static String tag ( dPlayer player , dNPC npc , String arg , boolean instant , ScriptEntry scriptEntry ) { } public static String tag ( dPlayer player , dNPC npc , String arg , boolean instant , ScriptEntry scriptEntry , boolean debug ) { } public static String tag ( String arg , TagManager . TagContext context ) { if ( arg == null ) return null ; if ( ( ( arg . indexOf ( '>' ) ) == ( - 1 ) ) || ( ( arg . length ( ) ) < 3 ) ) return TagManager . cleanOutput ( arg ) ; if ( ! ( context . instant ) ) arg = arg . replace ( "\\<" , String . valueOf ( ( ( char ) ( 1 ) ) ) ) . replace ( "\\>" , String . valueOf ( ( ( char ) ( 2 ) ) ) ) ; int [ ] positions = TagManager . locateTag ( arg ) ; if ( positions == null ) { return TagManager . cleanOutput ( arg ) ; } int failsafe = 0 ; do { failsafe ++ ; ReplaceableTagEvent event ; if ( positions == null ) break ; else { String oriarg = arg . substring ( ( ( positions [ 0 ] ) + 1 ) , positions [ 1 ] ) ; event = new ReplaceableTagEvent ( context . player , context . npc , oriarg , context . entry ) ; if ( ( event . isInstant ( ) ) != ( context . instant ) ) { arg = ( ( ( ( arg . substring ( 0 , positions [ 0 ] ) ) + ( String . valueOf ( ( ( char ) ( 1 ) ) ) ) ) + ( TagManager . escapeOutput ( event . getReplaced ( ) ) ) ) + ( String . valueOf ( ( ( char ) ( 2 ) ) ) ) ) + ( arg . substring ( ( ( positions [ 1 ] ) + 1 ) , arg . length ( ) ) ) ; } else { Bukkit . getServer ( ) . getPluginManager ( ) . callEvent ( event ) ; if ( ( ( ! ( event . replaced ( ) ) ) && ( ( event . getAlternative ( ) ) != null ) ) || ( ( event . getReplaced ( ) . equals ( "null" ) ) && ( event . hasAlternative ( ) ) ) ) event . setReplaced ( event . getAlternative ( ) ) ; if ( context . debug ) dB . echoDebug ( context . entry , ( ( ( ( "Filled<seq2seq4repair_space>tag<seq2seq4repair_space><" + ( event . toString ( ) ) ) + "><seq2seq4repair_space>with<seq2seq4repair_space>'" ) + ( event . getReplaced ( ) ) ) + "'." ) ) ; if ( ! ( event . replaced ( ) ) ) <START_BUG> dB . echoError ( ( ( "Tag<seq2seq4repair_space>'" + ( event . getReplaced ( ) ) ) + "'<seq2seq4repair_space>is<seq2seq4repair_space>invalid!" ) ) ; <END_BUG> arg = ( ( arg . substring ( 0 , positions [ 0 ] ) ) + ( TagManager . escapeOutput ( event . getReplaced ( ) ) ) ) + ( arg . substring ( ( ( positions [ 1 ] ) + 1 ) , arg . length ( ) ) ) ; } } positions = TagManager . locateTag ( arg ) ; } while ( ( positions != null ) || ( failsafe < 50 ) ) ; return TagManager . cleanOutput ( arg ) ; } private static int [ ] locateTag ( String arg ) { } public static List < String > fillArguments ( List < String > args , ScriptEntry scriptEntry ) { } public static List < String > fillArguments ( List < String > args , ScriptEntry scriptEntry , boolean instant ) { } public static List < String > fillArguments ( String [ ] args , dPlayer player , dNPC npc ) { } }

Fix:
dB . echoError ( ( ( context . entry ) != null ? context . entry . getResidingQueue ( ) : null ) , ( ( "Tag<seq2seq4repair_space>'" + ( event . getReplaced ( ) ) ) + "'<seq2seq4repair_space>is<seq2seq4repair_space>invalid!" ) ) ;